Lots of energy in a moving car. Hit a curb or something that points it upwards, pretty easy to get air (wrecking the front in the process) the top gear double loop is done at 25 mph.
Get real though he's not done 30mph in order to come off a bend in the wrong direction (normally you'd expect him to wash out to the left/outside of that bend not end up to the right) take off and land firmly planted in some one's front room
.
Now say he was doing 30 and needed to avoid something which causes him to jinx right, unless he's a complete numpty who has confused the accelerator for the brake pedal, at 30mph he mounts the curb and takes down the hedge and nestles against the bimmer at worst (retarding affect of all 3 plus some actual braking).
Of course your brakes only work if your tyres are in contact with the ground
cars tend not to get too airborne for too long at normal driving speeds
Unless the unfortunate sod hit a thermal right after he clipped the curb. Damn those thermals be crazy